This invention relates to a wire harness for an automotive vehicle, in which a plurality of insulator-sheathed electric wire elements are juxtaposed on a plane and are provided at suitable positions with connectors, and relates to a method and an apparatus for producing the wire harness.
Electrical appliances in an automotive vehicle are electrically interconnected through wire harnesses. For convenience of explanation a typical example of the conventional wire harnesses is described below by referring to FIGS. 11 to 13B. FIG. 11 is an explanatory view of a conventional wire harness. FIG. 12 is a perspective view of a conventional plat electric wire. FIGS. 13A and 13B are explanatory views of a conventional method for branching the wire harness.
A typical conventional wire harness, as shown in FIG. 11, has a plurality of insulator-sheathed electric wire elements a and connectors c attached to the wire elements a. However, a work of inserting every wire element a into the connector individually is troublesome and raises a cost of the wire harness.
Consequently, a so-called flat electric wire P shown in FIG. 12 has been utilized. Since this wire P is made of a plurality of single core electric wire elements a juxtaposed integrally, the elements a are not separated from each other and thus the wire is easy to handle. Further, this wire is useful since insulator displacement terminals can be connected to the wire elements at a time (see FIGS. 13, 2A, and 2B).
However, the electric wire P, as shown in FIG. 12, has an integrated insulator sheath for each wire element a and thus is very expensive in comparison with the same number of single core insulator-sheathed electric wire elements a. It is desirable to produce the electric wire P (wire elements a) as inexpensively as possible since the wire harnesses are used in so many circuits.
In the event that the wire harness W is arranged, for example, from a joint box B to each electric appliance D, as shown in FIG. 11, the number of the wire elements a is decreased as they are away from the joint box B. When such wire harness W shown in FIG. 11 is formed by using the flat electric wire P shown in FIG. 12, insulation displacement terminals t shown in FIGS. 13A and 13B are usually utilized to connect each wire element a to the connector C. At this time, the wire element a' (FIG. 13A) which extends over a branch becomes useless. Although such useless wire element a' should be removed from the wire harness in view of a cost, the removement process of the insulator-integrally-sheathed electric wire P will raise a cost.
Also, positions of the insulation displacement terminals t at the respective branching portions are not adjacent to each other but at random, as shown in FIGS. 13A and 13B. The positions of connector terminals in the joint box are different from those of the terminals in the branching connector C on account of the respective electric appliances of different makers. Thus, it will be understood from the drawings that distances between the terminals t to be simultaneously brought into insulation displacement contact are different and an insulation displacement work for the terminals are complicated. If the distances between the terminals are constant, the work will be simplified. If the distances between the terminals are different, there may be necessary wire elements a between the wire elements a to be cut and thus this results in a difficult work of removing the useless wire element a'.